Sofa



FIG. 1 is a top, left side, front perspective view of a sofa showing my new design;

FIG. 2 is a front perspective view thereof;

FIG. 3 is a rear perspective view thereof;

FIG. 4 is a left side perspective view thereof;

FIG. 5 is a right side perspective view thereof; and,

FIG. 6 is a top perspective view thereof.

The heavy broken line showing of portions of the sofa in FIGS. 1-6 forms no part of the claimed design. The additional thinner broken lines in the figures are for the purpose of illustrating portions of the sofa, which form no part of the claimed design. 

CLAIM The ornamental design for a sofa, as shown and described. 